Table 1.

Schematic representation, polarization components, notations, symmetry, space group and basis vectors in the mono-domain phase model. (Adapted with permission from [24], Copyright 2009 Springer)

	Polarization components	Notation	Symmetry	Space group	Basis vectors
	P1 = P2 = P3 = 0	paraelectric	Tetragonal	P4/mm	[100], [010], [001]
	P1 = P2 = 0, P3 ≠ 0	c phase	Tetragonal	P4mm	[100], [010], [001]
	P1 ≠ 0, P2 = P3 = 0	a phase	Orthorhombic	P2mm	[100], [010], [001]
	P1 = P2 ≠ 0, P3 = 0	aa phase	Orthorhombic	C2mm	[110], [110], [001]
	P1 = P2 ≠ 0 < P3 ≠ 0	r phase ( MA)	Monoclinic	Cm	[110], [110], [001]
	P1 = P2 ≠ 0 > P3 ≠ 0	r phase ( MB)	Monoclinic	Cm	[110], [110], [001]
	P1 ≠ 0, P2 = 0, P3 ≠ 0	ac phase ( MC)	Monoclinic	Pm	[100], [010], [001]
	P1 = P2 = P3 ≠ 0	Fo	Monoclinic	Cm	[110], [110], [001]